Charging base



FIG. 1 is a top plan view of a charging base showing the claimed design;

FIG. 2 is a front view of the charging base (both the front and left side views being mirror images);

FIG. 3 is a right-side view of the charging base (both the right side and rear views being identical);

FIG. 4 is a bottom view of the charging base;

FIG. 5 is a top front perspective view of the charging base;

FIG. 6 is a top, rear, right side perspective view of the charging base; and,

FIG. 7 is a bottom perspective view of the charging base.

The dashed broken lines depict portions of the charging base that form no part of the claimed design. 

CLAIM The ornamental design for a charging base, as shown and described. 